This application makes reference to, incorporates the same herein, and claims all rights accruing under 35 U.S.C. xc2xa7119 through my patent application entitled Device and Method for Detecting Presence of Ink Cartridge earlier filed in the Korean Industrial Property Office on the 21st day of October 1997 and there duly assigned Serial No. 1997/53946.
1. Field of the Invention
The present invention relates to an ink jet printer and, more specifically, to a device and a method for detecting the presence of an ink cartridge in an ink jet printer.
2. Background Art
An ink jet printer performs the printing operation by moving a carriage, containing an ink cartridge, back and forth during the printing process. To ensure accurate printing the carriage is often brought to a standard position to begin the printing process. To increase the quality of printing it is important that the carriage firmly hold the ink cartridge, thus allowing the print head of the ink cartridge to be accurately positioned. Upon powering the printer, a controller causes the printer to carry out an initialization procedure that starts with positioning the carriage at a predetermined position, also referred to as the home position.
Sometimes, however, the printing operation may be attempted without an ink cartridge being installed in the carriage. This can happen when a used ink cartridge is being replaced with a new ink cartridge, but the user inadvertently forgets to install the new cartridge prior to powering the printer. Contemporary methods of determining the presence of an ink cartridge can result in the consumption of power or the contamination of the interior of the printer.
I believe that it may be possible to improve on the contemporary art by providing a method and a device for detecting the presence of an ink cartridge that does not require an additional sensor beyond that needed to initialize the carriage, that is economical to manufacture and does not reduce the efficiency of assembly of ink jet printers, that does not increase the power consumption of the printer, that does not result in the contamination of the interior of the housing, and that is easy to repair and maintain.
Accordingly, it is an object of the present invention to provide an improved device and an improved method for detecting the presence of an ink cartridge in an ink jet printer.
It is another object to provide a device and a method for detecting the presence of an ink cartridge in an ink jet printer that does not require an additional sensor, beyond that needed for the proper initialization of the printer.
It is still another object to provide a device and a method for detecting the presence of an ink cartridge in an ink jet printer that does not increase the power consumption of the printer.
It is still another object to provide a device and a method for detecting the presence of an ink cartridge in an ink jet printer that does not result in the contamination of the interior of the housing.
It is yet another object to provide a device and a method for detecting the presence of an ink cartridge in an ink jet printer that is easy to repair and maintain.
It is still yet another object to provide a device and a method for detecting the presence of an ink cartridge in an ink jet printer that is economical to manufacture and does not reduce the efficiency with which the devices can be assembled.
To achieve these and other objects, a device and a method are provided for detecting the presence of an ink cartridge in an ink jet printer. The device can be operated with a regular ink jet printer. Inside the ink jet printer is a reciprocating carriage that transports an ink cartridge across a cut sheet of printable medium to form images on the cut sheet. The carriage may have a first blade on it that is aligned to pass a light emitter and a light detector that are mounted along the path of travel of the carriage. The combination of the first blade and the light emitter and light detector can be used to initialize the printer after the printer has been turned on. Once the printer is powered the computer moves the carriage until the first blade comes between the light emitter and light detector. Then, the controller can determine that the carriage is in the starting position, also referred to as the home position. To allow the controller to determine whether there is actually an ink cartridge in the carriage a second blade may be placed on the ink cartridge. When the ink cartridge is properly mounted in the carriage the first blade and the second blade are both positioned in a common geometric plane. Thus, after the controller has confirmed the position of the carriage, the carriage continues to move a predetermined distance in the direction it was moved to initialize the printer. If a cartridge having a second blade passes through the light emitter and light detector then a detect-signal is sent to the controller. If the controller receives a first detect-signal, representing the position of the carriage, and does not receive a second detect-signal, representing the second blade of the ink cartridge, after moving the carriage a predetermined distance, then an error-signal is sent out by the controller to alert a user to the absence of an ink cartridge in the ink jet printer.
A method for detecting the presence of an ink cartridge in an ink jet printer starts with powering on a printer. Second, the carriage is moved until it reaches the home position. After the carriage has been initialized, the carriage continues to move for a predetermined distance. If the pair of optical scanners detects the second blade of the ink cartridge then a second detect signal is sent to the controller. Otherwise, an error signal is sent from the controller to alert a user that the ink jet printer requires the insertion of an ink cartridge.